1. Field
This disclosure relates generally to semiconductor processing and more specifically, to trace routing within a semiconductor package substrate.
2. Related Art
Within semiconductor packages, metal traces are used in the package substrate to communicate signals between the semiconductor die and the circuitry external to the semiconductor package, such as to a printed circuit board (PCB). Typically, it is desirable to match the delay of these metal traces with each other in order to increase the timing margin of the interface between two semiconductor devices (such as two semiconductor devices connected to a PCB). Extra delay can be achieved by implementing longer trace routing that is compacted in length by lateral zig-zag routing within a single metal layer, which is typically referred to as “serpentine” or “meandering” routing. However, this type of lateral routing requires greater area within the single metal layer, which may not be available. For example, the lateral routing may block needing routing room of other traces.